New guy here, but wanted to share my experience. I was stopped by TSA at WA's SeaTac airport because of snap caps. I had flown in with handguns, ammo and snap caps with no problem. I tried to explain that they were solid aluminum and not ammunition (I had them with my toiletries, not in the locked gun case to differentiate). Low man TSA said supervisors were out to lunch and just throw them away. "Sure. You guys can pay me the $12 for them" which got him literally spinning trying to figure out where and who to talk to. I even recommended the POLICEMAN a few yards away. Nope.
Missed my flight. Got the Supervisor to agree they were inert pieces of metal. They still had me duct tape them together to simulate "packaging". But the pocket knife next to the toothpaste was not an issue.

Justin